Conductive polymers have been widely investigated due to growing interest in their use in, e.g., anti-static coatings, conductive paints, electromagnetic shielding, electrode coatings and the like. Polyaniline is a relatively air-stable conductive polymer which has previously been prepared by oxidative polymerization of aniline monomer in aqueous media by ammonium persulfate or potassium dichromate. The use of doped, i.e., protonated, polyaniline has been limited by its intractability, i.e., it decomposes without melting and is essentially insoluble. Undoped polyaniline has low solubility in polar solvents such as dimethylformamide, dimethyl sulfoxide, n-methylpyrrolidinone, and also in 80 percent by weight formic acid or acetic acid (see Angelopoulos et al., Mol. Cryst. Liq. Cryst., 1988, 160. 151-163). However, the undoped polyaniline is not electrically conductive.
Recently, another conductive polymer, polypyrrole, has been prepared in a colloidal or latex form by the use of water-soluble polymers, such as poly(vinyl alcohol-co-acetate), poly(vinyl pyrrolidone), and methyl cellulose, as polymeric surfactants or steric stabilizers.
Accordingly, it is an object of this invention to provide a processable electrically conductive polymer composition containing a polymerized amino-substituted aromatic monomer such as aniline.
It is a further object of this invention to provide a processable electrically conductive latex polymer composition.